Is there a formula to calculate GPH?

Skybound

Well-Known Member
Hello, I built a 4 site aeroponic system from an 18 gal Rubbermaid tote. The manifold sits roughly 4" below the bottom of the net pots and has 12 micro sprayers threaded into it. Each sprayer is rated to 25 PSI. Is there a formula I can use to calculate what size pump I'd need to effectively keep pressure behind the sprayers? Another thread suggested over shooting and just after the pump, insert a Tee with one side to the manifold and the other side to a shut off valve to dial in blow off pressure to not overload the manifold and little sprayers. though I may do this anyway as it will create an undertow in the res which will aid in keeping nutes thoroughly mixed during run time of the pump, I still have no way of knowing what would be adequate, let alone what would constitute as overkill. Anybody have a clue?

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1 psi = .454 feet of head.
for pvc youd would also have to find out your friction losses for each fitting and pipe.
then you get a pump curve and find the appropriate pump for the feet of head you need.
i think each sprayer would have a friction loss to..
As far a GPH goes thats where you need a pump curve.. you line up the feet of head and the GPH on a specific pump. i dont think there's any caculation for it - its just pump specific.
wayyy to complicated.

if you're using a centrifugal pump like the ones most people use for hydro you wont get a ton of pressure because they arent positive displacement pumps, yes you can get high pressure ones but they're way more expensive. (Grundfos would be an example)

you would probably want to look into an accumulator tank + ro pump/diaphram pump + solenoid valve with a 24v xformer + a relay or timer...

Im no messiah of this stuff, but i know a lot about hot water heating systems.. still working on getting my first aero grow up and running here also.. I was auctially going your route there too with the tote but im not sure you need such a big root chamber. not sure yet though.. we'll see.. starting my second attempt here in about 2 weeks.
 
On this particular tote, the lid is recessed 1", each not pot is 4" tall, from the bottom of the net pot to the sprayer line is 3.75" and the manifold itself is 7.5". I figure the res will be roughly 7", maybe less. I tried to split the space apart to address all concerns, i.e. root aeration, adequate reservoir, space between each plant, ease of access and for some reason I strongly feel that lifting the lid of the res for any reason is a major concern. So I plan to fill/drain externally as well as monitor level and pH/TDS externally also. Here is a more concise plan for my bucket, maybe it will give you an idea or 2.
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Thanks, but I did not yet buy a pump. I planned for a 250, but wanted to know for sure before I part with the presidents. The pump is all I need to complete my res system. Lights and blower are next on the list. Pick'in up little things here and there from home depo and the local hydro store.

Picture a guy that has nothing but wants everything for next to nothing, that's me.
 
I have some similar setups based on StinkBuddies original designs. They recommend around 400 gph for that size system with that number of spray heads. I think I'm using 395 gph EcoBoost pumps. I've been using aeroponics for a few years, and I would suggest that you don't need to water from the top. The sprayers below will be sufficient to supply the plants.
 
I just today got a 550 GPH ActiveAqua. In the feedline I have a 1/2 - 1/4 - 1/2 tee to shoot some blow off pressure out to mix the sauce every time it sprays, but I also wanted to plan for the future as I might include an external res down the road. we'll see.
 
Hey Skybound, I have a aeroponic system very similiar to yours. Mine is DIY. I started with two 30 gal. resevoirs and made 4 grow sites in the lid for 6" net pots. I lined the outer edge of the lid with plastic that hangs to the inside of the reservoir because my sprinklers were blowing a little water to the edge resulting in leaks outside my reservoir. I have a 370 gph pump and 2 - 12" aerators in each tub. I started with my pump timer 15 min on 90 off 8 x day. After the roots hit the DWC mark I turned my timer to 15 min on 240 min off 4 x day. I use Fox Farm nutes and 1000w HPS for budding. I didn't see the need for the drip system because I veg my plants under CFLs and use the drip then. I still use bubble ponics for extra seedlings that I can't bring myself to get rid of. My preference so far is the DWC/Aeroponics combo.

Urban Poison x 8 under 1000w HPS.
DWC/Aeroponics 1 week flowering
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6 weeks into flowering
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HDR, that's wicked setup you got there. After re-contemplating the space I have to work with, I cut the lid to hold 2 - 5" pots. I fired it all up 2 days ago to clean it out with dish soap and water and noticed I did not place most of my sprayers too wisely so I added 2 more on top at a severe angle to make sure the baskets get wet too, and just as the pump connects to the PVC via 1/2" barb, I put one upside down to stir the juice up every time the pump fires up. When I get my bucket into rotation (in about 2 months after a soil plant is harvested) i will use your schedule. Thanks for that bro!! Though I have a 400w MH/HPS setup, I can't use that at this location so it will collect dust until I can find a better spot with more square feet. I got a question, what do you keep the temp of your res at? I have a DIY means to slowly cool, or rapidly cool if need be, and I suppose I could also heat it if tasked to do so. I have 2 - 6" PC radiators and 120mm PC fans that align perfectly, so building my own heat exchanger would only require me to get some pex tubing, maybe a copper coil, and another water pump. Anyway, I enjoyed your setup. Check out my journal to see mine. Only a single unsexed plant now with 4 clones taken yesterday and 5 schwag seeds all in rockwool in the dome. Thanks again for sharing.
 
Hey Sky, Honestly I don't worry too much about alot of details because I'm lazy. I don't test my water anymore because I know what I need to do tomake my ph correct with the water I use (I distill my own water). The temp of my res stays around 70-75. The temp at my canopy is 80-85. It all depends on how technical you want to get. I have a heater for propagation that's about it. I let my water acclimate to room temp before I use it. I grow indoors in a temp controlled enviroment so I figure my water is ok. Again, you can spend alot of money if you want. I have probably less than 3k in fixtures, ventilation, tables, co2, etc.
Here's my bubble ponic girls. I think I lost one from letting water level drop too much. Its in the back.

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Seedling Table with the drip system
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Happy Growing. Keep me posted on your progress.
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